Electric sound-reproducing apparatus



Jan. 7, 1930. A, A THOMAS 1,742,832

ELECTRIC SOUND REPRODUCING APPARATUS Original Filed Dec. 29, 1926' 2Sheets-She et i INVENTOR Jan. 3336. A. A. THOMAS I 1,742,832

ELECTRIC SOUND REF PRODUCING APPARATUS 1 Original Filed Dec. 29, 192 2Sheets-Sheet 2 Patented Jan! I930 v I I i lJNlTED STATES PATENT O AnoLrnA. THOMAS, or NEW YORK, 1v. Y. nnncrarc souma-aaraonucme APPARATUSApplication filed December 29 1826, Serial No. 157,633. Renewed April24, 1929.

My invention is-for an electric phonograph Fig.5 shows in transverse.cross-section a and other sound-reproducing apparatus of modifiedconstructionof lid; novel construction, iii which a loudspeaking Fig. 6represents diagrammatically a form diaphragm constitutes a structuralpart of of transmission system between the electric the lid or otherclosure of the cabinet or outer reproducerand the loudspeakingdiaphragm, casing in whi'chthe operative mechanism is including a switchcontrolled by a rheostat mounted. When my invention is applied in armfor 0 ening the battery circuits; the construction ofelectricphonographs, no Fig. 7 shows in plan view a modified conhorn oramplifying chamber is required, and struction of phonograph havinga-cylindrieal 10 the entire phonographic mechanism may be casing,portions of the constructlon being oused in a small case that is easilycarried broken away to show certain parts; about. With propertransmission connec- Fig. 8 is a transverse cross-section on line tionsbetween the electric reproducer and the 88 of Fig. 7; and loudspeakingdiaphragm, it is possible to Fig. 9 is a diagram of another form of avean inexpensive portable machine capa-- transmission system between theelectric re-" 05 ble of full-toned reproduction comparing producer andthe loudspeaking diaphragm.

- favorably with that of high-priced cabinet efore proceeding with adetailed descripphonographs. tion of the drawings, I want to explainthat In a ,preferred form of my invention as I have purposelyexaggerated the dimensions 20 applied to electric phonographs, I employan of certain parts for the sake of clearness, so

electric reproducer of flat construction, lying that the illustrationsare not to be considered horizontally close to the record and-thus conasshop drawings. tributing toward a cabinet of reduced height. Referringto Figs. 1 and 2, there is a box- Another feature of my invention is fora like cabinet or carrying case indicated as a volume-controlling devicehaving means to whole by O, which in the present instance is cut out allcircuits when the machine is not of rectangular shape and is adapted tobe in use. I y easily carried about. In the broader aspect So that myinvention may be fully underof my invention, any practical form ordestood by those who are skilled in this art to sign of cabinet may beemployed, but in cerenable them to practice the same, I have setaininstances I prefer a cabinet consisting lected several illustrativeembodiments for of a bottom section 10, a middle section 11, a detaileddescription. I want it understood, and a top section or lid 12. Thesections 10 however, that the specific constructions shown and 11 arehinged together at 13, and lid 12 in the accompanying drawings are notto be is hinged to section 11 at 14. Suitable locks 35 regarded in'thenature of restrictions or limior latches 15 and 16 hold the sections ofthe tations, but rather as practical examples of cabinet in closedposition when needed. If my invention. In these drawingsdesired, thecabinet1may be provided with a Fig. 1 shows in plan view anelectricphono-' suitable carrying handle (not shown). The graph of the portableor table type constructintermediate section 11 of the cabinet has a 40ed in accordance with In invention, the lid motorboard 17, from whichdepends a motor of the case being thrown ack;

Fig. 2 isa transverse cross-section on line way. The motor 18 may bemechanical or 22 of Fig. 1, with the lid in closed position; electrical.In the present case I have assumed Fig. 3 is an enlarged plan view ofthe electhe motor to be mechanical, and so I have in- 45 tric reproducershown in Figs. 1 and 2, the dicated a crank 20 for winding up the motortop plate being removed to show the parts springs. If the motoris'electrical, it ma 7 within; a v be driven from a battery housedwithin the Fig. 4 is a transverse cross-section on line cabinet, or itmay be operated from the houseof Fig. 3, the top plate being shownatlighting circuit through suitable electric con- 50 tached; nections,which are well understood by those familiar with this art. As phonographmosame and coil 39 in fixed position within the tors, both mechanicaland electrical, are readreproducer casing. Two leaf springs 42 and ilyobtained in the market in various sizes 43 are arranged in the casing toengage the and styles, I need not show or describe any extension 34 ofneedle arm N at opposite 5 structural details of motor 18. points, asindicated-at 44 and respectively. On motorboard 17 is mounted an arm 21The upper spring 42 is secured to the cylinivoted at its rear end toswing horizontally drical wall of the casing at 46, and the lower overthe turntable and also to have movement spring 43 is secured at 47 tothe bottomplate in a vertical plan A simple way of mount- 27 of thecasing. The contact oints 44, and m ing the arm 21 is by means of ahollow stand and 45 of the two springs are su stantially in 22 fixed onthejmotorboard and supporting a vertical alignment, so that the springsexert horizontally rotatable post 23 which has 9. equal and oppositepressures on the needle air (if trunnions 24. The arm 21 is provided armto hold the same in normal predeterwith a transverse hub or bearing 25adapted mined osition, as indicated in Fig. 4. The 15 to be supportedbetween the trunnions 24-1501 to 1 dis 28 of casing 26' carries a pairof invertidal movement. The swivel 0st 23 persu ated binding posts 48 towhich are conmits free horizontal movement 0 the arm 21- nected theleads 49 of coil 39. Similarly, the Any other practical form of mountingfor bottom disk 27 has a pair of insulated bindthe arm 21 may beemployed. The free end ing posts 50 for receiving the leads 51 of coil2() of this arm carries an electric reproducer in- 37, The leads 51being of very fine wire and g5 50 horizontal arm 34. The arm 33 is ahollow th i ht, amount dicated as a whole by It. This reproducer isreadily flexible, do not interfere with the viof flat construction, soas to occup minimum bratory movements of the stylus lever.

space in a vertical direction and t ereby per- The operation of electricre roducer R will mit a reduction in the height of the cabinetbe clearfrom the preceding dbscription, and

as For this purpose, the reproducer R consists of may briefly, bedescribed as follows, reference a flat casing 26 having a bottom plate27 and bein had to Fig. 4. As the needle or stylus a top plate 28. Thecasing 26 is prefera l 35 v1 rates laterally in the record groove,thecylindrical 30f pill-box shape, I might sayi long arm 34 vibrates in avertical plane and and is PIOVl ed witharadially extending hll coil 37moves toward and away from fixed so 39 adapted to fit over the free endof supp r coil 39. Assuming that coil 39 is traversed by as ing arm 21.The lates 27 and 28 ma be sepaa primary current and that coil 37 isproperly rate disks secure to the cylindrica body of connected incircuit in an amplifying transthe casing, or one of these parts may 08smission system, it is clear that the movements integral with the casingstructure.' Suitable of coil 37 with respect to fixed coil 39 will in-35 means,such asa screw 30,- seeures the reproduce secondary currentimpulses in the circuit '100 ducer casing rigidly t0 the supporting a m,of coil 37 in accordance with the vibrations which is preferably a smalllight-tube (as of of the stylus point. The induced secondary aluminum,brass, etc.) adapte to conceal the impulses in coil 37 may be amplifiedin any connecting wires that run from the repropractical wayto operate aloudspeaking dia- 40 ducer to the transmission system below the phragm,as will later be ex lained more in t b d. The reproducer casing 26,detail. It will be observed rom Fig. 4 that which is best made of lightnon-magnetic Imthe vibrations of the stylus 35 are mechaniterial, isprovided with a pair of lateral1y p r cally transmitted to coil 37 inamplified ratio, jecting ears 31, which carry sultable bearmg which inthe present instance is about 1: 3.

45 members 32. These bearing members, whi h The coil 37 is very lightand does not appremay be adjustable pointed screws, support a ciablyincrease the inertia of stylus lever N, stylus arm indicated as a wholeby N. Thls which responds without hindrance to the sinarm is in theshape of a bellcrank lever comnations of the record groove. The springs42 'prising a short vertical arm 33 and a long and 43 are so made andadjusted as to exert of mechanical impedance on cylindrical part adaptedtorecelve and supthe stylus arm. The absence of a magnet report a stylus35, which may be a needle or any duces the weight of the reproducer, andthere other practical member for engaging in is practically no magneticdrag on the stylus record groove. The horizontal arm 4: f arm, as inthese prior constructions where an 55 stylus leverNextends into thecasing through armature vibrates in a magnetic field. By 12 a slot 36.The free inner end of arm 34 cararranging the springs 42 and 43 so as toexries a small cylindrical cell 37, whlch 1S l'lgtend in oppositedirections and yet have their idly attached in any practical way, as bycontact points at the same distance from the means'of a small plate 38.On the top plate pivot of the stylus arm, I am able to use 28 of casing26 is fixed a coil 39 in Substantmlspringsof considerable length in asmall shal- "12 A ly axial alignment with coil 37. Qoil 39 is l epreferably rovided with a magnetic core 4 In Fig. 2, the reproducer Rand supporting for intensi ying the magnetic effect of the arm 21 areindicated in playing position by coil. A screw 41, which may be ofmagnetlc dotted lines R and 21', a record 52 being 65 material, engagesthe core40 to secure the shown on turntable 19. In order to hold 4inside face of the formed with radial arms 58, which termi-' thereproducer arm 21 in firm position when the machine is carried about, Iprovide a suitable support or rest, which may simply consist of a pairof spring fingers 53 mounted on the motorboa'rd and adapted to hold thetubular arm 21 clamped between them, as shown in Figs. 1 and 2.

The hinged lid 12' is provided with a circular opening 54 in which isfitted an annular frame 55. This frame has radially extending lugs 56adapted to receive fastening screws 57 for securing the frame to thelid. The frame 55 is nate in a cylindrical support 59 adapted to receivean electromagnetic driving unit 60. A cross-shaped piece or spider 61 issecured b screws 62 to the arms 58 for rigidly hol the driving unit 60'against the circular shoulder 63 of support 59, as best shown in Fig. 2.Any other practical means may be used for securing the driving unit 60in proper position on the supporting frame 55. A loudspeaking diaphragmD, most conveniently made in cone form, is mounted on the circular frame55, so as to cover com letely the opening 54 in the lid. The diap ragm Dis fixed in position by being clamped between the annular frame 55 andaring 64, which forms part of a grille or open shield parts 55 and 64together, with the diaphragm D rigidly clamped between. A link or rod 67connects the apex of the diaphragm with the electromagnetic driving unit60. As such units are well known in the art, it will not be necessary toshow or describe any structural details thereof, and it is sutlicient tosay that the link 67 represents any practical operative connection,whether me-' chanical or magnetic, between the driving unit and thediaphragm.

It will be clear from Fig. 2 that the cone diaphragm D constitutes thegreater part of lid 12 and forms a portion of the outer wall of thephonograph cabinet. Putting this differently, it may be said that thetop of lid 12 consists of a vibratory wall D, which functions as aloudspeaking diaphragm. 13y so mounting the cone diaphragm D that 1tsapex extends outwardly, the supporting frame 55 and the parts carriedthereby are substantially flush with the inner face 68 of lid 12, exceptfor the lugs 56 which need only be a small fraction of an inch inthickness. This construction permits the use of a carrying case orcabinet of comparatvely small height. The different parts carried bfythe supporting frame 55 are secured to the rame before the latter isattached to lid 12, there- 75 carrying case or cabinet C are mounted theelectric devices that go to make up the system' for transmitting with orwithout amplifica'tion) the electric impulses produced by reproducer Rto the driving unit 60. In Fig. 2.1 haye shown, by way of example, a

. battery 69 and an amplifying transformer 70, but it will be understoodthat such other parts are mounted in the chamber below the motorboardasare required for the particular transmitting and amplifying systemselected by the designer. If the reproducer R is of the electromagnetictype, as above described, the feeble electric impulses produced by thereproducer R is connected in the circuit of battery 69. The primary coil71 of transformer 70 is also connected in the battery circuit in serieswith reproducer R. It may be supposed that the microphone re roducercomprises a flat cylindrical casing mounted horizontally on itssupporting arm Screws or rivets 66 secure the annular 11k e casing 26 ofthe electromagnetic reproducer R. Since the'phonograph of Figs. 1 and 2may have either type of electric reproducer, reproducer R may be mountedon arm 21 in lace of reproducer R. The secondary coil 2 of transformer70 is connected with driving unit 60. and amplifies the current impulsesin primary coil 71 suf-' ficiently to cause the driving unit to operatehragm D with requisite elficiency. Am-

'ng transformers for this purpose are easily constructed or may bebought in the market.

The machine of Figs. 1 and 2 is best operated with the diaphragm lidopen, but it may also be operated with the lid closed. In the latterevent, the cabinet ought to have soundopenings above the motorboard, asindicated at 17, to prevent damping of thediaphragm and to allow thesound-waves produced by the bottom face of the dia hragm to issue freelyinto the outer air. may be covered with gauze or otherwise rentieredinconspicuous; or they may be formed in an ornamental grille comprisingpart of the outer cabinet structure.

.The volume of reproduction in the system of Fig. 6 is controlled by arheostat 73 having a pivoted conducting arm 74 turned bya knob on themotorboard. Arm 74 carries a dia pli brush or contact member 76 forengaging the r reslstance element 73. One end of this reslstanceisconnected to one side of the battery through a conductor 77. The arm 74is connected by a conductor 78 to circuit lead 79.

he openings 17.

board and with a recess 89.

-When the rheostat arm is in I that lid 12' and all Between the points80 and 81 of the battery circuit is connected a switch S consisting of afix'ed contact 82 and a movable spring contact 83. A; conductor 84 leadsfrom point 80 to 5 contact 82, and a conductor 85- connects the sIpringcontact arm 83 with conductor 78. he spring arm 83 is mounted on asuitable insulating support 86, which may conveniently be secured to theunderside of motor- 17. The normal set or tension pf s ring 83 is suchthat the switch is closed. he rheostat arm 74 carries at its free end acam head or projection 87. The s ring contact 83 is formed with anincline offset 88 As long as the rheostat arm 74 engages the resistance73, the switch contacts 82 and 83 remain closed and the battery currentflows through the reproducer and the primary coil 71. It will be noticedgo'that th'erheostat is shunted across the battery 69. Consequently,when the rheostat arm is in position 74,'the maximum amount of currentis shunted-around the battery and the. volume of reproduction isweakest. position 7 4", the resistance of the shunt across the batteryis a maximum and most of the current flows through primary coil 71, sothat the reproduction is loudest. When the rheostat arm 74 is movedtoward the off position, as

shown in Fig. 6, the cam-head 87 strikes the inclined portion 78 ofcontact arm 83 and moves it away from the fixed contact 82. As

r soon as the cam-head 87 enters the recess 89 of spring 'maticallylocked against further movement contact 83, the rheostat arm is autointhe same direction, and the contact 83 is thus held in open position.This breaks the circuit throng primary coil 71 and rheostat cessedportion 89 of spring contact 83 is such that the rheostat arm is easilymoved out of the recess by a slight turning pressure of the fingers onknob 75.

In Fig. 5 the cone diaphragm D is mounted in the top of lid 12' by meansof a frame 90 adapted to be inserted into the lid from the outside. Forthis purpose, the lid 12' is formed with an annular ledge or should er91 for receivin the ring 92 of frame 90. The diaphragm is secured toring 92 in the same way as in Figs. 1 and 2. I shall not thereforerepeat that part of the preceding description. Frame 90 is formed withan annular flange 93 which fits into the opening 94 of lid 12'. From thebase of the annular shoulder 94 project radial arms 95, which are theequivalent of the radial arms 58 in Figs. 1 and 2. The circularsupporting frame 90 and "all its parts are secured to lid 12' by screwsor bolts 96, orother suitable fastening devices. Otherwise, what hasbeen said about frame of Figs. 1 and 2 is applicable to frame 90 of Fig.5. It is to be supposed parts mounted thereon attached to the lid fromthe outside and rest against a 73, The shape of cam-head 87 and the re--sound waves are reenforced by may be substituted for lid 12 in Fig. 2.The mam difference between the constructions in Fi 2 and 5 is that inFig. 2 the frame 55 an the attached parts are secured to the inner faceof the lid, w ile in Fig. 5 the frame 90 1s firmly seated on the annularledge 91. Such parts as are common to Figs.v2 and 5 are indicated by thesame reference numerals.

In the modification ofFigs. 7 and 8, the cabinet or carrying case C 1sof cylindrical shape. In this instance, the lid consists of a circularframe 97 having an extension 98 to provide a hinged connection 99 withthe b y of the case. The extension 98 may be formed with a depending lug100 adapted to shoulder 101 on the case when the lid is thrown o n inupright position, as indicated by dotte lines in Fig. 8. The circularframe 97 is provided with radial arms 102 adapted to support the drivingunit 60, as explained in detail in connection with Figs. 1 and 2. Theloudspeaking diaphragm D is mounted on frame 97 by means of a clampingring 103, which is secured to frame 97 by screws 104 or otherwise. Theclamping ring 103 carries a dome-shaped panel 105, which performs thedouble function of shielding the diaphragm D against injury anddeflecting sound waves through openings 106 into the outer air. Themember 105 may also be described as forming a recessed chamber 107,open-at its periphery to the outer air and housing the diaphragm D. Theparts 103 and 105 are referably cast or molded as a single piece, eingconnected only by short radial arms 108. The outer wall of dome 105 maybe colored and ornamented to suit the taste of the designer. To permiteasy lifting of the lid, the annular frame 97 is formed with afinger-piece 109. When the lid is in open upright position, the soundwaves produced by the front face of the diaphragm are projectedforwardly, and these the sound waves produced by the rear face ofdiaphragm D and projected into the outer air by the domeshape member105. If the machine is to be operated with the lid closed, it isdesirable to provide the upper portion of casing C with sound openingsof ample area, as indicated by dotted lines 110. If the machine is to beused only in the home and is not intended to be transported like a pieceof hand luggage, the outer casing wall above the motorboard may consistwholly or partly of ornamental grille work through which the sound wavespass easily "'to the outer air when the machine is operated with the lidin closed. position. In that event, the soun waves produced by thediaphragm will issue partly through the grille work of the easing andpartly through the annular passage 106 at the circumference of member105.

In the chamber 111 below the motorboard V Fig. 9 an ampllfyingtransmission system be-' the usual way through filament primary coil 121of 17 are housed the various tute the transmission system between thereroducer and the driving unit. The rectan ar outline 112 is supposed torepresent a 53y battery consisting 0 Su essary to feedthe requiredcircuits in any particular transmission system that ma be selected. Byway of example, I have s own in tween the electromagnetic reproducer Rand the diaphragm D. The fixed primary coil -39 is connected in thecircuit of battery 113, Which operated by the rheostat arm, as describedin reference to Fig. 6., The secondary coil 37, which is mounted "on thereproducer arm, is connected at one end to the grid 115 of an amplifyingvacuum tube V. The other end of coil 37' is connected to one side of-the filament 116 through a conductor 117. Thefilament 116 is fed by abattery 118 and controlled by a rheostat 119 in the usual way. In thecircuit of the plate battery 120 is the primary coil 121 of transformerT, one end of this coil being connected to the plate electrode 122 oftube V. The plate circuit is completed in 116 and conductor 123. Thesecondary coil 124 of transformer T is connected to the driving unit 60.

The operation of the amplifying transmission system illustrated in Fig.9, will be clear to those familiar with the radio art, and so I needonly say that the electric impulses produced'in coil 37 by the vibratorymovements of the stylus arm cause voltage variations in the grid 115.These voltage variations produce amplified transformer T, and theseamplified impulses are transmitted by the secondary coil 124 to thedriving unit 60; Fig. 9 has been drawn as simpleas possible, omittingcondensers and might be found necessary or desirable to improve theclarity and volume of reproduction. The use of such devices iswell'known to those who are familiar with audio amplifying systemsemployed in the radio art.

Although I have indicated only one audio amplifying tube in Fig. severalstages of amplification maybe used. In Fig. 7, the dotted outline Vrepresents the vacuum tube of Fig. 9, and it is supposed that this tubeis properly supported in cham-" her 111. In Fig. 8 the transformer .T isrigidly mounted in chamber 111. The batteries 114, 118 and 120 of Fig. 9are properly supported in casing C, and they may be representeddiagrammatically as a whole by the rectangular outline 112. By placingthe batteries 112 at the rear of case 0' opposite the carrying handle125, the stability of the closed case is increased. when the same is setdown on the base provided by the straight extensions 126 and 127 on thetop and beti,-m,aaa

parts that constimgs in the motorbo ch cells as are nec-" I board to themay be shunted by a controlling rheo \stat 114 and a cut-out switchvention that I have a greater degree by using chair for playing,

current impulses in the inductances that 9, it isobvious that tom of theouter case. Access to the arts in chamber 111 may be had either throngopenard or through doors in the outer wall of casingCf below the motor-J- I ard This will be understood without the need of additionalillustration. The'wires 128 in Fig. 8 nections may be led from-below themotor-; ing with the o ening and closing of the lid. In the finishedmachine this wiring may be concealed.

It will be clear. from the foregoing "description of several embodimentsof my in-.

phonograph in which all the mechanismnecessary for loud;reproduction ismountpd in a small cabinet or box that is easily carried about. Bymaking the diaphragm a structural part of reduce the height of thecabinet considerably, and this advantage is I the flat reproducer whichconstitutes one of my invention. An electric phonograph contained in asmall vportable-z'box, and yet capable of reproducing with.the great-vol-' ume and fine tonal quality of large cabinet indicate how theelectrical 6011-.

driving unit 60 Without interfere 1 provided an electric 5' the hd, itis possible to realized to even 7 of the features machines fills thecrying need of those who dwell in city apartment houses where the roomsare small and space is scarce. My new instrument may be placed on atable or and when not in use it is easily tucked away in a closet orotherwise disposed of in a small space, like a hat box or suitcase.-Portable mechanical phonographs are not capable of giving a loud clearreproduction, owing to the necessarily small amplifying chamber, andtherefore my invention possesses a usefulness wanting in those priormachines. Furthermore, my new phonograph may be manufactured at a muchlower cost than large cabinet machines ing substantially the same or nobetter re production. Of course, my invention is not limited to electricphonographs of the portable type, for the various features abovedescribed may be embodied in a lar e household cabinet, or the smallcase containin the phonograph mechanism may be mounte on, or form partof, a cabinet having compartments for holding records or used for otherhousehold purposes.

The cylindrical case C of Figs. 7 and 8 may be constructed in threeparts like the Figs. 1 and 2. systems of Figs. 6

giv-'.

{my invention and not by wa or limitation.

' art without departing invention as defined in Althou gh I haveshownand described certain specific constructions, I want it understoodthat I have done so merely to explain of restriction Changes anmodifications will doubtless occur to those skilled in the from thescope of the the following claims: I I claim as my invention:

a '1. An electric phonograph comprising a cabinet, a frame hinged at thetop of said cabinet, a loud s eaking diaphragm secured at its edge tosaid frame and forming therewith a lid for said cabinet, whereby saiddiaphragm is open to the outer air when said frame is in closed positionon the cabinet, an electric reproducer, and operative connectionsbetween said reproducer and said diaphragm.

2. An electric phonograph comprising a cabinet having a hinged frame atthe top provided with an opening, a loudspeaking diaphragm secured atits edge around said opening and covering the same, whereby saiddiaphragm forms an outer part of a lid for the cabinet, anelectromagnetic drivin unit carried by said frame for operating saidiaphragm, an electric reproducer, and electric transmission connectionsbetween said. reproducer and said unit.

3. A portable electric phonograph comprising a carrying case having ahinged top lid formed by a loudspeaking diaphragm secured at its edge toa part of the lid structure, and electric repro ucing mechanism foroperating said diaphragm, which is open to the outer air when the lid isclosed.

i. In electric sound-reproducing apparatus, a cabinet havin a hinged lidformed in part by a cone diap ragm, the apex of said diaphragmprojecting outwardly, said diahragm being open tothe outer air when theidisclosed.

5. An electric phonograph comprising a cabinet having a hinged lid, aloudspeaking diaphragm secured at its edge to a part of the lidstructure and forming an outer wall of said lid so that said diaphragmis open to the outer air when the lid is closed, an electromagnetic unitcarried by said lid for operating said diaphragm, and electricreproducin mechanism for operating said unit.

6. l n electric sound-reproducing apparatus, a cabinet having a lidformed in part by a cone diaphragm, and a substantially conical ordome-shaped disk carried, by said lid over said diaphra m to deflectsound waves, said disk also shielding said diaphragm.

7 .'Anelectric phonograph comprising a cabinet, a frame hinged .at thetop of said cabinet and provided with an opening, a;

cone diaphragm mounted on said frame so as to close said opening,'theapex of said diaphragm projecting outwardly, said frame and diaphragmforming a lid for the cabinet, whereb said diaphragm is open to theouter air w en said lid is closed, an electromagnetic unit carried bysaid frame for operating said diaphragm, an electricreproduceroperatively supported in said cabinet, and means fortransmitting the electric impulses of said reproducer to said drivingunit, said diaphragm and driving unit permitting closure of the lid.

8. An electric phonograph comprising a cabinet having a hinged sectionprovided with an opening, a frame securedvto said section and forming arigid structural parfl thereof, a loudspeaking diaphragm mounted on saidframe and coverin said opening, whereby said diaphragm forms an outerstructural part of the cabinet, and is open to the outer air when saidframe is in closed position on the cabinet, an electromagnetic unitcarried by said frame for operating said diaphragm, and electricreproducing mechanism for operatin said unit.

9. An electric p onograph comprising a cabinet having a hinged sectionon top provided with an opening, a frame secured to saidsection, a conediaphragm mounted on said frame and covering said opening, the apex ofsaid diaphragm projecting outwardly, said hinged section and diaphragmforming a lid for the cabinet, whereby said diaphragm is open to theouter air when said lid is closed, an electromagnetic unit carried bysaid frame for operating said diaphragm, an electric re roduceroperatively supported on the motor oard of the cabinet, and means fortransmitting the playing action of said re producer to said drivingunit, said frame and the parts carried thereb lying substantially abovethe lower edge of said hin ed section so that the lid may be closed witout interference by said reproducer.

10. In an electric phonograph, an electric reproducer circuit includinga battery, a rheostat shunted across said battery for controlling thevolume of reproduction, said rheostat having a pivoted arm manuallyadjustable, a switch in said battery circuit, said switch including aspring contact arranged to be actuated by said arm into open positionwhen the arm is turned into a certain position, said spring contactautomatically moving into c1rcuit-closing position when said arm isturned to volume-controlling position, and

means whereby said spring contact when Q trically connected with saiddriving openmg, means for section o ned b theii ward swmgm' of said midle s ection for'ea y access to said electric arts, a top or lid sectionhinged-to the middle section and carr driving unit therefor, and anelectric reproducer mounted on-said turntable and elec-' unit throughsaidtransmission s stem. 12. An electric phonograp comprising a cabinetrovided on top with a hinged section having an annular opening, a framehaving a ring fitted around the edge of said securing said ring to saidsection a cone diaphragm secured at its edge to said ring with the apexof the diaphragm pointing outwardl said section and dia hragmconstituting a inged lid for the cabinet, a grille fitting over saiddiaphragm and having an annular flange secured to said ring, the edgeofsaid diaphragm being rigid- 1y clamped between saidringand flange,

v radial arms extending from said ring and movement from t stylus.

terminating at the center in a support, an

electromagneticunit mounted in said support for operating said diaphrasaid frame and all parts carried there y being from said secand electricretion as a unitary structure,

operating said reducing mechanism for riving unit. p

13. In an electric phonograph having an arm pivoted for horizontalswinging movement and also for vertical movement, an electric reproducercomprising a shallow casing fixed in horizontal position on the free endof said arm, a bellcrank lever pivoted to said casing so as to vibratein a vertical plane, said lever consisting of a horizontal arm and avertical arm, means provided on said vertical arm to support a stylusfor lateral vibra-- tion, and electric reproducing means in said casingoperatively connected to the free end of said horizontal arm, whichreceives vertical e lateral vibrations of the 14. In an electricphonograph having an arm pivotedfor horizontal swinging movement andalso for vertical movement, an.

electric reproducer comprising a shallow casing fixed in horizontalposition on the free end of said arm, a bellcrank lever pivoted to saidcasing so as to vibrate in a vertical plane, said lever consisting of along' horizontal arm and a short vertical arm adapted to support astylus for lateral vibration, whereby the stylus vibrations aretransmitted as vertical movements to the free end of said horizontal armin amplified ratio, and electric reproducing means in said casingoperatively connected to the free end of said horizontal arm.

15. In an electric phonograph having an arm pivoted for horizontalswinging movement and also for vertical movement, an electric reproducercomprising a shallow cas- 'ng a loudspeaking diaphragm and anelectromagnetic ing fixed in horizontal position on the free end of saidarm, a pivot sup ort and a slot at the edge of said-casing, a ellcranklever mounted on said support to vibrate in a vertical plane,said leverconsistin of a horizontal arm extending through said slot into thecasing and a vertical arm adapted to support a stylus, said arms beingso proportioned that the stylus vibrations are transmitted to the innerend of said horizontal arm in amplified ratio, electric reproducin meansin said casing operatively connecte to the inner end of said horizontalarm, and a pair of horizontally arranged spring blades in said casingfor engaging said horizontal arm on top and be low, said spring bladesopposing each other to hold said bell-crank in predetermined normalposition.

16. An electric phonograph reproduced for lateral-cut records comprisinga casing adapted to be mounted on a supporting arm, a bellcrank leverpivoted substantially at its apex to said casing so as to vibrate in avertical plane, said lever comprising a vertical arm and a horizontalarm, means on said vertical arm to support a stylus for lateralvibration, whereby the stylus vibrations are transmitted to saidhorizontal arm as sub stantially vertical movements there-oi, and

electric reproducing means in said casing controlled bythe verticalmovements of said horizontal arm.

17. In electric sound reproducing apparatus, a case or cabinet having anouter hinged wall formed in part by a loudspeaking diaphragm, which thusconstitutes an outer structural part-of said case or cabinet, the edgeof said diaphragm being rigidly connected to said hinged Wall, anelectromagnetic unit carried by said hinged wall for actuating saiddiaphragm, and electric mechanism in said case for operating said unit.

18. An electric phonograph reproducer comprising a flat cylindricalcasing adapted to be secured flatwise to a swinging support, ahorizontal arm carried by said casing and pivoted to vibrate in avertical plane, a needle holder pivotally mounted on said casing tovibrate laterally for playing lateralcut records, said needle holderbeing arranged at one side of the casing so as to be freely accessible,means for connecting said needle holder to said means in said flatcasing operated by the movements of said arm, and resilient means forholding said arm in predetermined normal position. 1

19. An electric phonograph reproducer comprising a fiat cylindricalcasing adapted to be fixed in substantially horizontal posi-- tion onthe free end of a horizontally swinging support, a bellcra'nk leverpivoted substantially at its apex to said casing so as to vibrate in avertical plane, said lever comprising a vertical arm and a horizontalarm,

arm, electromagnetic means on said verticalearm to sup it 'a stylus forlateral vibration, whereb t e styhis vibrations are transmitted to saihorizontal arm as vertical movements thereof, a pair of coils mounted,horizontally in said casing, means for prodiicing relative movement ofsaid coils by the vibrations of said arm, and resilient means fornormally holding saidcoils in predetermined normal position. 10 ADOLPHA. THOMAS.

